Apparently when some handsets start to get overly warm, the display develops a rather unpleasant yellowish tint.

Sony acknowledged the problem in a statement: "Sony Mobile Communications has identified that the display on a limited number of Xperia S smart phones may show a slight yellow tint if exposed to temperatures above 40 degrees Celsius."

The company stressed that this was an issue which only affected a small number of Xperia S handsets, and was due to a fault in the manufacturing process which has now been corrected.

Those unfortunate enough to have purchased a phone which exhibits these symptoms can contact Sony customer services, and the firm will sort a replacement.

The company noted: "Sony Mobile Communications will resolve this at no cost to the consumer."

The Xperia S has a rather nice screen - a 4.3 inch LED backlit "reality display" which is 720p resolution - so it's a shame to see it marred by such an issue. On the other hand, it's good to see Sony admitting and resolving the problem in short order.

Sony's new smartphone hasn't got off to a flying start, given that there have also been reports of some customers experiencing an issue with the Xperia S whereby the GPS function isn't working properly.